This invention relates to a process for the treatment of alkoxyalkanols. More particularly, this invention is directed toward a process for the cleavage of a terminal --CH.sub.2 OH moiety from an alkoxyalkanol at elevated temperatures in the presence of a catalytically effective amount of heterogeneous nickel. The resulting compounds are referred to herein as methyl-capped alkoxylates.
Methyl-capped alkoxylates find use as solvents or as low foam detergents for industrial applications. Since these detergents are composed only of the elements carbon, hydrogen and oxygen, they do not pose the environmental problems which stem from detergents containing such heteroatoms as nitrogen, sulfur or phosphorus. However, in the production of the methyl-capped alkoxylates, the ether linkages in the alkoxyalkanol starting materials degrade easily at elevated temperatures; a mild, selective process for production of the methyl-capped alkoxylates is thus of commercial interest.
Rylander, "Organic Synthetic with Noble Metal Catalysts," (1973) discloses on page 269 the dehydrogenation and decarbonylation of primary alcohols upon heating with a catalyst. There appears no disclosure of nickel catalysts or alkoxylated alcohols however.
U.S. Pat. No. 3,894,107 discloses the conversion of alcohols to hydrocarbons over a zeolite catalyst impregnated with a metal cation from Groups I-VIII. U.S. Pat. No. 3,920,766 teaches the conversion by simultaneous dehydration and hydrogenation of t-butanol to isobutane over a supported nickel catalyst. Neither of these patents disclose a process which yields a product with one less carbon atom than the reactant alcohol.
U.S. Pat. No. 3,501,546 discloses the conversion of alcohols with n carbon atoms to hydrocarbons with (n-1) and (2n-1) carbon atoms over a palladium on titanium dioxide catalyst. The presence of water is said to favor products with (2n-1) carbon atoms.
U.S. Pat. No. 4,139,496 teaches the steam dealkylation of alkyl-aromatic hydrocarbons over a supported alumina catalyst containing oxides of nickel, potassium and chromium, with at least a portion of the nickel being in the form of free metal.
Badin, Journal of the American Chemical Society, Vol. 65, pages 1809-13 (1943), shows the liquid phase conversion of primary aliphatic alcohols into the corresponding aldehyde, an unsaturated hydrocarbon of one less carbon atom and the saturated hydrocarbon of one less carbon atom. The catalyst employed was Raney nickel.